For example, Harry's name references his leadership qualities, while Ron's pertains to his role as a sidekick. "Harry" is the middle-English version of "Henry," a name popular among English kings through the centuries. For "Ronald," Rowling seemingly looked to the Old Norse "Rögnvaldr," a title for a ruler's adviser. In contrast, Hermione's name, taken from Shakespeare's "The Winter's Tale" (and Greek mythology, more broadly) has less to do with her own traits than with her Muggle parents' desire to pick a clever moniker.

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You never know when inspiration will strike ― and Rowling jotted down the Hogwarts house names on an airplane vomit bag.

Inspiration hit on a plane.
Warner Bros Studios

Many people, celebs included, strongly identify with a specific Hogwarts house. You might be surprised to learn, then, that Rowling first wrote down the words Gryffindor, Slytherin, Ravenclaw, and Hufflepuff on the back of an airplane vomit bag. She revealed this tidbit on Twitter in 2017.

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Harry Potter was named for his great-grandfather.

This is how it intersects with "Fantastic Beasts."
Warner Brothers

According to Pottermore, Harry Potter shares a name with his great-grandfather. Although this ancestor ― who lived in the late 19th century and early 20th century ― doesn't appear in the books, his timeline would intersect with the "Fantastic Beasts" era. Here's hoping for a cameo in the spin-off series.

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The magical plants in the series all come from a real-life compendium of flora.

Mugwort and toadflax are real.
y-studio/ iStock

At a glance, plant names like "Mugwort" and "toadflax" sound like words pulled from Rowling's boundless imagination. But these flora actually exist in the Muggle world. As the author explained in an interview with CBS' "60 Minutes," the plants in the series come from a compendium called "The Complete Herbal" by English botanist and herbalist Nicholas Culpeper.

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But only one character in the Harry Potter universe is a figure from Muggle history.

Nicolas Flamel is also a real person.
Warner Bros Studios

Nicolas Flamel, the eponymous sorcerer from "Sorcerer's Stone," was a French businessman and scribe born in the 14th century. The real Flamel's connection to alchemy, embellished after his death, is at best tenuous.

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Edinburgh, Scotland, where Rowling resides, provided a ton of inspiration for the series.

Edinburg inspired Hogwarts.
f11photo/Shutterstock

Scotland's capital is teeming with Gothic architecture, cobblestone streets, and narrow passageways. Rowling was enchanted by the city's locales, from Greyfriars Kirkyard― where the "real" Tom Riddle is buried ― to George Heriot's School, a private institution whose turreted building inspired Hogwarts.

You can even visit the cafes where Harry's story began, namely The Elephant House, the so-called "Birthplace of Harry Potter" ― be sure to check out the bathroom, which is covered in Potter-centric graffiti left by fans over the years ― and Spoon, a restaurant that Rowling frequented in its former incarnation as Nicolson's Cafe.

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Even Stephen King was freaked out by Dolores Umbridge.

King was scared by Umbridge.
IMDb/Warner Bros.

Forget Voldemort ― one-time Defense Against the Dark Arts professor Dolores Umbridge has been deemed one of fiction's creepiest villains by none other than Stephen King.

Like the multitude of spells in the series, Hogwarts' official motto is also in Latin.

Latin plays a big part in the world.
Warner Bros.

It's no secret that Rowling, who studied Classical languages and mythology at Exeter University, is familiar with Latin. Not only do the series' many spells come from that ancient language ― so does Hogwarts' motto, "Draco dormiens nunquam titillandus" ("Never tickle a sleeping dragon").

"You know the way that most school slogans are things like persevere and nobility, clarity, and fidelity or something, it just amused me to give an entirely practical piece of advice for the Hogwarts school motto," Rowling explained in a 2005 BBC interview.

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The movies featured an animal production team.

There were lots of animals around.
Warner Bros.

Magical creatures aside, there were a slew of ordinary animals in the Harry Potter movies ― and they were overseen by a separate animal production team. Four different owls played Harry's bird, Hedwig, while over a dozen rats portrayed Ron's pet rodent, Scabbers.

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The "Harry Potter" books have been translated into 80 languages, from Albanian to Hebrew to Scots.

Harry Potter is available in basically every language.
Kirsten Acuna / Business Insider

It may be hard to imagine someone other than Daniel Radcliffe as Harry, but the role could have been played by another actor.

Haley Joel Osment could have been Harry Potter.
Warner Bros.

Prior to a creative row with Rowling, Steven Spielberg was pegged to direct "Sorcerer's Stone" ― and he wanted Haley Joel Osment (of "Sixth Sense" fame) to play the Chosen One. In fact, Daniel Radcliffe beat out more than 300 child actors for the part of a lifetime, according to The Telegraph.

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Peeves, the mischievous Hogwarts ghost, was supposed to appear in the films.

Peeves didn't end up making an appearance in the film.
Chioric/Shutterstock

One of the most notable differences between the books and the movies is the absence of mischievous Hogwarts ghost Peeves from the film adaptations.

The late British comedian and actor Rik Mayall was actually cast as the poltergeist in "Sorcerer's Stone" — but director Chris Columbus cut Mayall's scenes after a few weeks of shooting because he didn't like the look of the character onscreen.

But there was a secret, film-exclusive character hidden in the newspaper props designed for the movies.

Design firm MinaLima, which created fake newspapers for many of the films, hid a secret character in the magical periodicals. Known as the Ginger Witch, this elusive lady is a criminal whose escapades span decades.

First appearing in "Prisoner of Azkaban," you'll also spot her in the "Fantastic Beasts" movies.

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When she invented Dementors, Rowling drew from her past experiences with depression.

Rowling planned in advance who would meet a grim fate in the series — but she decided to spare one character's life at the last minute.

Character deaths are one of the narrative elements that Rowling plotted in advance. Originally, she planned for Ron's dad, Arthur Weasley, to meet a grim fate in "Order of the Phoenix" — but she changed her mind.

"I think part of the reason for that is there were very few good fathers in the book," she said in an interview with TODAY. "In fact, you could make a very good case for Arthur Weasley being the only good father in the whole series."

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To prevent early leaks of "Harry Potter and the Deathly Hallows," the series' publisher, Bloomsbury, gave the seventh and final book some quirky codenames.

The publisher hoped to keep book leaks to a minimum.
Warner Bros Pictures

Early proofs and print-outs of "Deathly Hallows" were given humorous red-herring titles such as "Edinburgh Potmakers" and "The Life and Times of Clara Rose Lovett: An epic novel covering many generations."

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Special effects in the films ranged from green screens to animatronics.

Not every special effect, however, was added post-production. Animatronics were used for creatures such as Professor Sprout's baby mandrakes and the "Monster Book of Monsters." There was also an animatronic Buckbeak used for close-up shots of the Hippogriff.

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The Quidditch brooms weren't your run-of-the-mill props.

The brooms had to be sturdy enough to be ridden.
Warner Bros.

The brooms were crafted from airplane-grade titanium.

"People think of them as a prop the kids are carrying around, but in reality, they have to sit on them. They have to be mounted onto motion-control bases for green-screen shots and special-effects shots, so they have to be very thin and incredibly durable," Eddie Newquist, chief creative officer of Global Entertainment Services — the firm responsible for The Harry Potter Exhibition ― told Popular Mechanics.